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171.
Simon Barquera Fabricio Campirano Anabelle Bonvecchio Lucia Hernández-Barrera Juan A Rivera Barry M Popkin 《Nutrition journal》2010,9(1):47
Background
Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. 相似文献172.
Jack A. Neal Betsy Booren Luis Cisneros-Zevallos Rhonda K. Miller Lisa M. Lucia Joseph E. Maxim Alejandro Castillo 《Journal of food science》2010,75(6):S319-S326
Abstract: The use of ionizing radiation for the control of foodborne pathogens and extending the shelf life of fresh iceberg lettuce and fresh spinach has recently been approved by the U.S. Food and Drug Administration. The efficacy of electron beam irradiation for controlling foodborne pathogens has been reported. For this experiment, the effectiveness of electron beam irradiation on the microbiological and sensory characteristics of fresh spinach was studied. Total aerobic plate counts were reduced by 2.6 and 3.2 log CFU/g at 0.7 and 1.4 kGy, respectively. Lactic acid bacteria were reduced at both doses of e-beam but grew slowly over the 35 d of the experiment. Yeasts and molds were not reduced in samples exposed to 0.7 kGy whereas 1.4 kGy significantly reduced microbial counts. Gas compositions (O2 and CO2) were significantly different than controls. Oxygen levels inside the spinach sample bags decreased over time; however, O2 levels did not drop below 1% that can induce anaerobic fermentation. CO2 levels for all treatments increased through day 4; yet 7 d after irradiation, CO2 level differences were not significant in both control and irradiated samples. Irradiation dose did not affect the basic tastes, aromatics, or mouth feels of fresh spinach, however; hardness attributes decreased as irradiated dose increased and slimy attributes of fresh spinach were higher in control samples compared to irradiated samples. 相似文献
173.
Shear behaviour of masonry has been deeply investigated for a lot of masonry types. Nevertheless, there is still a lack of knowledge on the shear response of tuff masonry, which is widely spread in the existing building inventory in seismic areas like as Italy, Turkey, and Japan. To characterize the non-linear behaviour of the unit–mortar interface within tuff masonry, a series of direct shear tests were carried out.In this paper, both experimental results and empirical formulae are presented. Classical shear strength and deformation parameters along with shearing fracture energy and dilatancy were characterized. A shear response surface including both stress–strain diagrams and the frictional strength model is proposed. 相似文献
174.
Susanna Esposito Alessia Scala Sonia Bianchini Alberto Zampiero Emilio Fossali Nicola Principi 《International journal of molecular sciences》2016,17(3)
In order to compare the last version of the Respiratory Virus Panel (RVP) Fast assay for human Adenovirus (hAdv) detection with a specific real-time polymerase chain reaction (qPCR), which is considered the gold standard for hAdv detection, nasopharyngeal samples collected from 309 children (age range, four months to eight years) with respiratory tract infection were tested using the RVP Fast v2 assay (Luminex Molecular Diagnostics, Inc., Toronto, ON, Canada) and a specific TaqMan qPCR to identify hAdv DNA. The RVP Fast v2 assay detected 30/61 (49.2%) hAdv infections that had been identified by real-time qPCR, demonstrating a significantly lower detection rate (p < 0.001). The sensitivity of the RVP Fast v2 assay in comparison to qPCR was lower in younger children (42.9% vs. 57.7%; Cohen’s kappa coefficient, 0.53); in samples with co-infections (40.0% vs. 56.7%; Cohen’s kappa coefficient, 0.52); and in samples with hAdv type C (45.9% vs. 57.1%; Cohen’s kappa coefficient, 0.60). Samples with lower viral loads were associated with a significantly lower sensitivity of the RVP Fast v2 assay (35.1% vs. 68.2%, p = 0.01; Cohen’s kappa coefficients, 0.49). The RVP Fast v2 assay has important limitations for the detection of hAdv and cannot be used to evaluate whether hAdvs are the main etiologic agent responsible for an outbreak or when epidemiological studies are performed. 相似文献
175.
In this paper, we develop the optimal minimum-energy scheduler for the dynamic online joint allocation of the task sizes, computing rates, communication rates and communication powers in virtualized Networked Data Centers (NetDCs) that operates under hard per-job delay-constraints. The referred NetDC’s infrastructure is composed by multiple frequency-scalable Virtual Machines (VMs), that are interconnected by a bandwidth and power-limited switched Local Area Network (LAN). Due to the nonlinear power-vs.-communication rate relationship, the resulting Computing-Communication Optimization Problem (CCOP) is inherently nonconvex. In order to analytically compute the exact solution of the CCOP, we develop a solving approach that relies on the following two main steps: (i) we prove that the CCOP retains a loosely coupled structure, that allows us to perform the lossless decomposition of the CCOP into the cascade of two simpler sub-problems; and, (ii) we prove that the coupling between the aforementioned sub-problems is provided by a (scalar) constraint, that is linear in the offered workload. The resulting optimal scheduler is amenable of scalable and distributed online implementation and its analytical characterization is in closed-form. After numerically testing its actual performance under randomly time-varying synthetically generated and real-world measured workload traces, we compare the obtained performance with the corresponding ones of some state-of-the-art static and sequential schedulers. 相似文献
176.
Roula Khadra Juan Antonio Sagardoy Suzan Taha Nicola Lamaddalena 《Water Resources Management》2017,31(13):4227-4238
A major shortcoming of Participatory Irrigation Management and Irrigation Management Transfer (PIM/IMT) is the absence of Monitoring & Evaluation (M&E) systems that accompany these processes and become a major instrument to correct, improve and learn. Although at the global level some countries have exerted efforts to implement M&E systems, these still present limitations, as the review of the international experiences shows. The Mediterranean situation is even more dramatic since only Tunisia implements an M&E system, whereas Egypt has shyly moved in this direction with a limited practical application. This state of affairs led the authors to develop a set of guiding principles to develop an M&E system to be applied in countries where PIM/IMT is adopted. This paper revises the main international efforts devoted to assess the performance of PIM/IMT and the state of the art of these processes in Southern and Eastern Mediterranean Countries. Moreover, it sets the framework and analyses the main sustaining factors for the development of a new M&E system for these countries. 相似文献
177.
Lucia D’Urzo Benedetto Bozzini 《Journal of Materials Science: Materials in Electronics》2009,20(7):666-670
In this paper we investigate the corrosive behaviour of various volatile organic compounds (VOCs) on electroplated copper.
The VOCs we considered were of the following types: (i) aromatic and substituted-aromatic compounds (benzene, toluene and
ethyl benzene); (ii) a chlorine-substituted hydrocarbon (dichloromethane) and (iii) an aliphatic alcohol (isopropyl alcohol).
Contamination by VOCs is typical of ULSI (Ultra Large Scale Integration) manufacturing environments, and exposure of Cu to
VOC-contaminated clean room air has been pinpointed as a serious cause of interconnects failure. SEM observation highlighted
corrosion signature that are typical of the different classes of molecules. In particular, the corrosion of copper is almost
absent following exposure to isopropyl alcohol, very slow in the case of aromatic molecules and severe in the case of dichloromethane.
The obtained results can be interpreted in terms of a crevice corrosion mechanism under droplets, enhanced by pitting in the
presence of chlorinated solvents. 相似文献
178.
179.
Nicola Buratti Claudio Mazzotti Marco Savoia 《Construction and Building Materials》2011,25(5):2713-2722
The present paper describes the results of an experimental investigation on the performances of concrete specimens reinforced with either steel or macro-synthetic fibres under three-point bending. Steel fibres are often used to improve the flexural toughness of concrete and are used in various structural applications while synthetic fibres are more often used to reduce crack opening due to shrinkage. Macro-synthetic fibres have been proposed more recently with the aim of creating an alternative to steel fibres in structural applications but their use is still limited.In the tests performed, specimens cast with the same concrete mix, but containing different dosages of either steel or macro-synthetic fibres, were used and compared. In general steel fibres were more efficient in increasing the toughness of concrete than macro-synthetic fibres, even though their results were significantly more scattered.Test results were used to calculate the parameters of stress-crack opening relations via inverse analysis using a cracked hinge model. This numerical model provided results, in terms of force-Crack Mouth Opening Displacement (CMOD) curves, in very good agreement with the experimental data. 相似文献
180.
Paolo Bertoldi Silvia Rezessy Eoin Lees Paul Baudry Alexandre Jeandel Nicola Labanca 《Energy Policy》2010
A number of Member States of the European Union (EU) have introduced market-based policy portfolios based on quantified energy savings obligations on energy distributors or suppliers, possibly coupled with certification of project-based energy savings (via white certificates), and the option to trade the certificates or obligations. The paper provides an up-to-date review and analysis of results to date of white certificate schemes in the EU. 相似文献